Widespread Vestibular Activation of the Rodent Cortex

Abstract

Much of our understanding of the neuronal mechanisms of spatial navigation is derived from chronic recordings in rodents in which headdirection, place, and grid cells have all been described. However, despite the proposed importance of self-reference information to these internal representations of space, their congruence with vestibular signaling remains unclear. Here we have undertaken brain-wide functional mapping using both fMRI and electrophysiological methods to directly determine the spatial extent, strength, and time course of vestibular signaling across the rat forebrain. We find distributed activity throughout thalamic, limbic, and particularly primary sensory cortical areas in addition to known head-direction pathways. We also observe activation of frontal regions, including infralimbic and cingulate cortices, indicating integration of vestibular information throughout functionally diverse cortical regions. These whole-brain activity maps therefore suggest a widespread contribution of vestibular signaling to a self-centered framework for multimodal sensorimotor integration in support of movement planning, execution, spatial navigation, and autonomic responses to gravito-inertial changes.

Head Movements Control the Activity of Primary Visual Cortex in a Luminance Dependent Manner

“…It has been suggested that retrosplenial cortex is a source of vestibular input to V1 4 . However, several other areas responding to vestibular stimulation have been shown to project to V1 3,25,26 . Also, the nature of the luminance input onto SOM cells remains to be established.…”

The role of GABAB receptors in the vestibular oculomotor system in mice

“…However, potential effects on visual-oculomotor system or vestibulo-spinal reflexes or somatosensory reflexes which are also important for maintaining posture and gait, remains unsolved. Furthermore, the vestibular neuronal projections are widely distributed throughout the brain areas such as thalamus, hippocampus and cortex including the amygdaloid nucleus [72-77]. Therefore, these profound vestibular neural processes may partially contribute to the drug-induced animal performance mediating general motor activities, body temperature, memory, learning or anxiety without affecting eye movements.…”

The anatomical boundary of the rat claustrum

“…The seeming absence of either 31 thalamic or hippocampal inputs suggest that the spatial coding in claustrum observed by Jankowski 32 and O'Mara (2015) is likely to be cortical in origin, perhaps originating from a combination of spatial 33 inputs from, e.g., grid cells of the entorhinal cortex (Hafting et al, 2005), and other inputs from 1 regions such as parieto-insular vestibular cortex (e.g. Rancz et al, 2015). The relative cortically-2 encapsulated inputs and outputs of claustrum we describe here would support this proposition.…”

“…The claustrum is a subcortical nucleus that exhibits dense connectivity across the neocortex. 2 Considerable recent progress has been made in establishing its genetic and anatomical 3 characteristics, however a core, contentious issue that regularly presents in the literature pertains to 4 the rostral extent of its anatomical boundary. The present study addressed this issue in the rat brain.…”